Relationships in lndian Araliaceae as inferred from sequences of Internal Transcribed Spacer (ITS) Regions of Nuclear Ribosomal DNA

Abstract

The Internal Transcribed Spacer (ITS) regions of nuclear ribosomal DNA were obtained from 42 accessions belonging to nine genera (Aralia, Brassaiopsis, Eleutherococcus, , Heteropanax, Macropanax, Merriliopanax, Panax, Schefflera and Tupidanthus) to assess relationships of Araliaceae in India. The ITS sequence data suggest two major clades of Indian Araliaceae: the Aralia - Panax clade and the Indian core palmate clade. The close relationship between Aralia and Panax was strongly supported with a bootstrap value of 89%. The two species of Panax (the ginseng genus) form a monophyletic group. Three sections of Aralia occur in India and the genus was strongly suggested to be monophyletic with sect. Dimorphanthus and sect. Pentapanax forming a subclade. Within the Indian palmate clade, the following monophyletic groups are detected: the Heteropanax-Schefflera-Tupidanthus group and the Eleutherococcus-Macropanax group. Merrilliopanax was found to form a clade with Brassaiopsis-Schefflera-Heteropanax-Tupidanthus. India is rich in species of Brassaiopsis. Our ITS phylogeny recognizes two groups within Brassaiopsis: 1. B. aculeata - B. glomerulata - B. hainla - B. mitis - B. shweliensis and 2. B. hispida - B. griffithii - B. simplicifolia.